<template>
    <div class="tags" style="display: flex" v-if="showTags">
      <div v-if="bool" class="btn-wrap" @mousedown="downFn(true)" @mouseup="upFn">
        <span class="el-icon-arrow-left"></span>
      </div>
      <el-scrollbar style=" flex: 1; height: 100%">
        <ul>
            <li class="tags-li" v-for="(item,index) in tagsList" :class="{'active': isActive(item.path)}" :key="index">
                <div @click="topath(item.path)" class="tags-li-title">
                    {{item.title}}
                </div>
                <span class="tags-li-icon" @click="closeTags(index)"><i class="el-icon-close"></i></span>
            </li>
        </ul>
      </el-scrollbar>
      <div v-if="bool" class="btn-wrap" @mousedown="downFn(false)" @mouseup="upFn">
        <span class="el-icon-arrow-right"></span>
      </div>
    </div>
</template>

<script>
    import bus from './bus';
    import Client from "../../assets/js/common.js";
    export default {
        data() {
            return {
                tagsList: [],
                timer: null,
                timer2: null,
                bool: false
            }
        },
        mounted(){
          this.hasScrollbar();
        },
        methods: {
        hasScrollbar() {
            console.log(222)
            let ele = document.getElementsByClassName("el-scrollbar__wrap")[0]
            if(ele) {
              this.bool= ele.scrollWidth > ele.clientWidth;
            }
            
          },
          downFn(type) {
            clearInterval(this.timer);
            this.timer = setInterval(() => {
              let b = document.getElementsByClassName("el-scrollbar__wrap")[0];
              let num = b.scrollLeft; 
              if(type) {
                if(num>0) {
                  b.scrollLeft -= 1;
                }
              }else {
                b.scrollLeft += 1;
              }
              
            },5)
          },
          upFn() {
            clearInterval(this.timer);
          },
 
          topath(str){
            let newStr = str.slice(1, str.length);
            let store = Client.getSession("path");
            let arr = [];
            for(let i=0; i<store.length; i++) {
              if(store[i].str == newStr) {
                arr = store[i];
              }
            }
            this.$router.push({path: str});
            this.$emit("myClick", arr);
            
          },
            isActive(path) {
                return path === this.$route.fullPath;
            },
            // 关闭单个标签
            closeTags(index) {

                const delItem = this.tagsList.splice(index, 1)[0];
                const item = this.tagsList[index] ? this.tagsList[index] : this.tagsList[index - 1];
                if (item) {
                    delItem.path === this.$route.fullPath && this.$router.push(item.path);
                }else{
                    this.$router.push('/');
                }
                this.hasScrollbar();
            },
            // 关闭全部标签
            closeAll(){
                this.tagsList = [];
                this.$router.push('/');
            },
            // 关闭其他标签
            closeOther(){
                const curItem = this.tagsList.filter(item => {
                    return item.path === this.$route.fullPath;
                })
                this.tagsList = curItem;
            },
            // 设置标签
            setTags(route){
                this.hasScrollbar();
                const isExist = this.tagsList.some(item => {
                    return item.path === route.fullPath;
                })
                if(!isExist){
                    // if(this.tagsList.length >= 8){
                    //     this.tagsList.shift();
                    // }
                    this.tagsList.push({
                        title: route.meta.title,
                        path: route.fullPath,
                        name: route.matched[1].components.default.name
                    })
                }
                bus.$emit('tags', this.tagsList);
            },
            handleTags(command){
                command === 'other' ? this.closeOther() : this.closeAll();
            }
        },
        computed: {
            showTags() {
                return this.tagsList.length > 0;
            }
        },
        watch:{
            $route(newValue, oldValue){
                this.hasScrollbar();
                this.setTags(newValue);
            }
        },
        created(){
            this.hasScrollbar();
            this.setTags(this.$route);
            // 监听关闭当前页面的标签页
            bus.$on('close_current_tags', () => {
                for (let i = 0, len = this.tagsList.length; i < len; i++) {
                    const item = this.tagsList[i];
                    if(item.path === this.$route.fullPath){
                        if(i < len - 1){
                            this.$router.push(this.tagsList[i+1].path);
                        }else if(i > 0){
                            this.$router.push(this.tagsList[i-1].path);
                        }else{
                            this.$router.push('/');
                        }
                        this.tagsList.splice(i, 1);
                    }
                }
            })
        }
    }

</script>

<style lang="less" scoped>
.btn-wrap {
  width: 30px; 
  height: 50%; 
  display: flex;
  align-items: center; 
  justify-content: center;
  span {
    font-size: 20px; 
    margin-top: 5px; 
    font-weight: bold;
  }
}
</style>

<style>
.el-scrollbar .el-scrollbar__wrap .el-scrollbar__view{
   white-space: nowrap;
} 
.el-scrollbar .el-scrollbar__wrap::-webkit-scrollbar {/*隐藏滚轮*/
display: none !important;
}

    .tags {
        position: relative;
        height: 60px;
        overflow: hidden;
        background: #fff;
        /* padding-right: 120px; */
        /* box-shadow: 0 5px 10px #ddd; */
    }

    .tags ul {
        box-sizing: border-box;
        width: 100%;
        height: 100%;
    }

    .tags-li {
        display: inline-block;
        margin: 3px 5px 2px 3px;
        border-radius: 3px;
        font-size: 12px;
        overflow: hidden;
        cursor: pointer;
        height: 23px;
        line-height: 23px;
        border: 1px solid #e9eaec;
        background: #fff;
        padding: 0 5px 0 12px;
        vertical-align: middle;
        color: #666;
        -webkit-transition: all .3s ease-in;
        -moz-transition: all .3s ease-in;
        transition: all .3s ease-in;
    }

    .tags-li:not(.active):hover {
        background: #f8f8f8;
    }

    .tags-li.active {
        color: #4491e0;
    }

    .tags-li-title {
        float: left;
        max-width: 80px;
        overflow: hidden;
        white-space: nowrap;
        text-overflow: ellipsis;
        margin-right: 5px;
        color: #666;
    }

    .tags-li.active .tags-li-title {
        color: #4491e0;
    }

    .tags-close-box {
        position: absolute;
        right: 0;
        top: 0;
        box-sizing: border-box;
        padding-top: 1px;
        text-align: center;
        width: 110px;
        height: 30px;
        background: #fff;
        box-shadow: -3px 0 15px 3px rgba(0, 0, 0, .1);
        z-index: 10;
    }

</style>
